Matrix: HB/494_bus
Description: S ADMITTANCE MATRIX 494 BUS POWER SYSTEM, D.J.TYLAVSKY, JULY 1985.
(undirected graph drawing) |
Matrix properties | |
number of rows | 494 |
number of columns | 494 |
nonzeros | 1,666 |
structural full rank? | yes |
structural rank | 494 |
# of blocks from dmperm | 1 |
# strongly connected comp. | 1 |
explicit zero entries | 0 |
nonzero pattern symmetry | symmetric |
numeric value symmetry | symmetric |
type | real |
structure | symmetric |
Cholesky candidate? | yes |
positive definite? | yes |
author | D. Tylavsky |
editor | I. Duff, R. Grimes, J. Lewis |
date | 1985 |
kind | power network problem |
2D/3D problem? | no |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 1,414 |
Cholesky flop count | 4.8e+03 |
nnz(L+U), no partial pivoting, with AMD | 2,334 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 1,776 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 3,446 |
SVD-based statistics: | |
norm(A) | 30005.1 |
min(svd(A)) | 0.0124224 |
cond(A) | 2.41541e+06 |
rank(A) | 494 |
sprank(A)-rank(A) | 0 |
null space dimension | 0 |
full numerical rank? | yes |
singular values (MAT file): | click here |
SVD method used: | s = svd (full (A)) ; |
status: | ok |
For a description of the statistics displayed above, click here.
Maintained by Tim Davis, last updated 12-Mar-2014.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.